(a) Temporary records with a retention period over 99 years. Agencies must use the microfilming requirements in §1238.14.

(b) Temporary records to be kept for less than 99 years, duplicates, and user copies. NARA does not require the use of specific standards for these microforms. Agencies may select a film stock that meets their needs and ensures the preservation of the microforms for their full retention period. NARA recommends that agencies consult appropriate standards, available as noted in §1238.3, and manufacturer's instructions for processing production, and maintenance of microform to ensure that the images are accessible and usable for the entire retention period of the records.